Depleted uranium (DU) has been a highly effective material for armor-piercing projectiles that are used against hardened targets and heavily armored vehicles. In addition to their high density and strength, DU kinetic-energy penetrators possess a unique ability to self-sharpen as they impact a target. This self-sharpening behavior is a result of adiabatic shear that occurs within the DU. Unfortunately, DU also possesses a certain low level of radioactivity and the use of DU penetrators is causing concern recently among those soldiers who are exposed to them.
Tungsten because of its comparable density would be an effective replacement for DU in kinetic-energy penetrators except for the fact that tungsten does not exhibit the self-sharpening behavior. Instead tungsten projectiles tend to flatten upon impact. In order to overcome the resistance of tungsten to form the shear bands that cause the self-sharpening behavior, it has been proposed to use nanostructured materials including nanocrystalline tungsten alloys and composites. Of course, the ability to fully investigate and implement these solutions depends to a degree on the availability of sufficient quantities of nanocrystalline tungsten powders.
Therefore, it would be an advantage to have a process to make nanocrystalline tungsten powders which could be used in such applications.